I was reviewing the source for Frantic this weekend and while I was going over the time-critical kernel loop:
KernelLoop: ; 70
lda #<DS_COLUP0 ; 2 72
sta WSYNC
KernelLoopNoWSYNC:
beq RepositionP0 ; 2 2
sta COLUP0 ; 3 5 - before 25
lda #<DS_COLUP1 ; 2 7
beq RepositionP1 ; 2 9
sta COLUP1 ; 3 12 - before 25
stx ENAM0 ; 3 15...
KernelLoop: ; 70
lda #<DS_COLUP0 ; 2 72
sta WSYNC
KernelLoopNoWSYNC:
beq RepositionP0 ; 2 2
sta COLUP0 ; 3 5 - before 25
lda #<DS_COLUP1 ; 2 7
beq RepositionP1 ; 2 9
sta COLUP1 ; 3 12 - before 25
stx ENAM0 ; 3 15...



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